Speedo/Leak/Stalling
 

I recently just bought a 1989 Impulse Turbo and she's got some issues.
1st off, her speedometer (and tripmeter and odometer) doesn't work. Everything else on the instrument cluster does work. I do have a replacement from an 87. Will that work and solve my issue, or do I not need it.
2nd, she leaks oil. Not a lot, but it's still some oil and I want to try to get that to stop. I think I saw it drip towards the back of the engine, closer to the center.
3rdly, she recently stalled on me on my way home from work. She attempted to twice and eventually did stalled within a span 20 minutes when I was coming to a stop/was stopped. I want to nip it in the bud asap so that doesn't continue.
Any bit of help or advice helps out tremendously. I love this car and want to keep her running for as long as I can. Thanks in advance